For the last few months I've had some heavy vibrations when I engage my clutch, its mainly when I start teh car or when I'm around the 4k rpm range. Could myy pressure plate be loose? I put a new clutch in about 4 months ago and did not resurface the flywheel but it just kinda started virbating now. it was a clutch from napa not a act or anything and I have the stock flywheel.

 

It could be "chatter" from the pressure plate not working right. When you replaced the clutch did you do the pressure plate too?

 

Maybe clutch disk has been deformed... just a little deformation can cause that...

But I bet it is the bearing-fork related problem... maybe something is shattering there...